Interlaminar Shear Stresses and Laminae Separation in a Disc

Abstract

The interlaminar shear stresses being higher in the posterolateral regions of the intact disc reinforces that, from clinical studies, tears originate in the posterolateral portion of the disc. The large interlaminar shear stresses, caused by asymmetry in the disc structure due to injury, along with chemical and structural changes in the disc with age, may be an important cause of further degeneration through laminae separation. This is the case for traditional composite laminates. This study points out the importance of interlaminar shear stresses to gain further understanding of the role of mechanical factors in producing disc degeneration, especially delamination of the anulus. Clinical relevance of the findings and possible relationship to the aging process are explored.